Room temperature superconductor discovered

Do you believe it or not? I suppose we shall know soon. If it is really true, something of this magnitude should snowball quickly.

Abstract
For the first time in the world, we succeeded in synthesizing the room-temperature superconductor (Tc ≥ 400 K, 127 oC) working at ambient pressure with a modified lead-apatite (LK-99) structure.
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Huge efforts are being undertaken to reproduce this result. Hold your horses until a lab can reproduce the Meissner effect which is key for superconductivity. So far it might be “just” a diamagnet.

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Says in the abstract they’ve demonstrated the Meissner effect?

But yeah … I’d like to think it’s real, but might be another Pons and Fleischmann. Or if might prove to be completely impossible to manufacture in quantity. Let’s hope for the best!

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There is a ton of drama with the coauthors which makes me think they really believe in it.

Two versions of the paper was published, one with 3 authors and one with 6. The one with 3 authors was published first, and the one with 6 just a few hours later. Note Nobel prize can only be given to 3 people.

The L in LK-99 said that the first paper was published by K without the permission of the other coauthors.

Lots of other drama too lol

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It’s just been posted to arXiv so far yeah?

Just skimmed the three-author one, but language-wise it looks to be quite a poorly written paper for the potential impact. Maybe they were in a rush?

Seems like some other discrepancies have been spotted too:

Another physicist, Douglas Natelson of Rice University, US, highlighted apparent inconsistencies in the two papers’ data on magnetic susceptibility, Χ. When Lee, Ji-Hoon Kim and colleagues placed their sample of LK-99 in a magnetic field, the six-authored paper states that the change in the material’s mass susceptibility (that is, Χ divided by density) amounted to 2.5 x 10-4 electromagnetic units per gram. “Assuming a density of about 7 grams per cubic centimetre, that gives Χ = –0.022, about 36 times that of graphite,” Natelson wrote in a Twitter/X thread dedicated to the findings. “That would be exciting, if it’s accurate.”

However, Natelson went on to note that “what appears to be the same data” also appears in Figure 4 of the three-authored paper, but with a completely different scale on the graph’s y-axis. This second set of numbers is, he said, “unphysical”, adding that the “pretty sloppy” discrepancy “does not encourage confidence in the results”.

My guess is the internal conflict made the three authors rush to submit something to ArXiv first so that they can stake their claim on it. The English quality doesn’t matter at the moment. If it is actually independently reproduced (and verified), they can always submit a better written version to a major conference, and secure multiple awards including an instant Nobel Prize.

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Someone from the field commented quite sceptical in this German language blog: Fefes Blog

Here’s an automated translation by deepl:

I work in the field and we discussed the preprint a bit in the research group this morning. In short, we don’t believe a word of it:
Fig. 1(a) and (c) are implausible. Normally something like this would look like this. Note the gradual increase at low currents, this effect is to be expected especially with magnetic fields.
Fig. 1(d) cannot be correct either. At Tc ~ 400K the Meissner effect would displace a much stronger field than 10 Oe = 1 mT. I.e. the distinction between FC (field cooled) and ZFC (zero-field cooled) should not be so pronounced. It should look more like this.
What the authors may mean is that they are outside the Meissner range, which can occur at higher magnetic fields (keyword: Type II superconductors). It would then look like this.
In this case, however, the temperature dependence does not match the critical currents of Fig. 1(a) and (c) at all.
And the fact that ALL values in Fig. 1(d) are negative is also extremely unusual, but this could perhaps be justified.
The data set in Fig. 4(b) is also a treat. It is VERY unusual if the heat capacity decreases again at high temperatures. This can happen at low temperatures, but not at high temperatures.
I know the described experimental setup / cryostat very well. There is no reasonable reason why the authors did not measure at higher temperatures to show that the behaviour above Tc ~ 400K is significantly different. E.g. a temperature dependence of the resistance would have been mandatory.
In general, the paper is very poorly written. The data are not sufficiently discussed, the explanations are poor, and the cited papers rather, shall we say, meagre. This does not inspire confidence in what the authors have measured and want to have seen.
My personal assumption is that the authors measured an insulator, accordingly no current flowed, and thus no voltage occurred (4-point measurement). Then it looks like a superconductor. But if you then turn up the current (i.e. the applied voltage), breakdowns may occur and a current starts to flow. That would explain the sudden increase.

If it’s BS, one has to wonder exactly why they would do it. They know what happens to people who publish fraudulent papers (well, anyone who publishes fraudulent papers outside of the pharma industry … :whistle: ). So what would be the point? It’d be a career-ending move.

P&F, back in the day, could have been legitimately mistaken. In this particular case, that doesn’t look like a possibility.

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An blog post providing an update on this:

https://www.science.org/content/blog-post/superconductor-update

My original hope was since the preparation of the material was relatively simple that replication of the material might be straightforward. This. . .has not been the case. Not anywhere even near the case. And the blame seems to sit firmly on the authors of the Korean preprints, from what I can see. If they do have something (and that’s very much open to doubt), they did an awful job of telling other people how to prove it for themselves. Numerous groups around the world tried the stated procedure in the days and weeks after the initial publication, and for the most part they got. . .heterogeneous junk. Tiny bits and scraps of this crud sometimes showed interesting behavior (in magnetic fields, for example) but no one really ever seemed to produce a clean (or even sorta-kinda-clean) bulk phase sample.

At this point it seems that there are (broadly speaking) two explanations for this situation. The first, which is far more likely at this point, is that the entire initial report was bungled and that there is no superconductor therein. That’s certainly the conclusion you’d draw from all the replication attempts, many of which have been from very serious and competent labs. The second, which is less likely but still possible, is that the Korean group has indeed made a superconductor but has (perhaps deliberately) not disclosed their best mode, because they care more about establishing a patent estate instead.

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Thanks for the update.

How sad. Let’s hope it is the second explanation that’s the right one; personally, I wouldn’t blame them if they wanted to chase a patent first. It’ll make them rich beyond anyone’s wildest dreams. Although one wonders why they didn’t just keep it very quietly to themselves, develop a halfway-workable production method, and not even bother announcing it with a scientific paper.

Especially that last part, as anyone can freely beat them to that, or the Nobel.

I’ve heard the procedure is out there, has anyone encountered it?

The Korean thing apparently turned out to be a “mistake”.

Another team were making the same claims. Turns out it’s another Pons and Fleischmann. There’s also a good discussion in this video of how scientific fraud happens, and how the culture in academia is skewed to encourage it.

Could also be a conspiracy by Big Copper, I suppose.

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Money and fame, same as any fraud really.

The research areas of Dias and Schon, superconductivity and electronics are very lucrative if you can make a name for yourself. There tons of money sloshing around for investment. Big breakthrough papers in prestigious journals get the attention of clueless investors.

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